Growth and characterizations of lead-free ferroelectric KNN-based crystals

Mythili Prakasam (1) , Philippe Veber (1) , Laetitia Étienne (1) , Oudomsack Viraphong (1) , Michel Lahaye (1) , Stanislav Pechev (1) , Eric Lebraud (1) , Kiyoshi Shimamura (2) , Mario Maglione (1)

1 ICMCB - Institut de Chimie de la Matière Condensée de Bordeaux
2 NIMS - National Institute for Materials Science

We have grown by flux method centimeter-sized single crystals from pseudo-hexanary Li2O–Na2O–K2O–Nb2O5–Ta2O5–Sb2O3 system. Based on chemical analysis, crystals of compositions (Li0.023Na0.583K0.394)(Nb0.925Ta0.037Sb0.038)O3 and (Li0.034Na0.609K0.357)(Nb0.896Ta0.047Sb0.057)O3 were characterized by X-rays diffraction which revealed a tetragonal structure. The dielectric analysis confirmed that the ferroelectric behavior of these crystals is very sensitive to little changes in composition as previously observed on ceramics. Such high flexibility of the ferroelectric properties in crystals opens the way towards improved understanding of the relations between structure and polarization in solid solutions which may be an alternative to the lead-based materials.

Mots clés: High temperature solution growth; Inorganic compound; Ferroelectric materials

Domaines: Matériaux; Chimie inorganique

Mythili Prakasam, Philippe Veber, Laetitia Étienne, Oudomsack Viraphong, Michel Lahaye, et al.. Growth and characterizations of lead-free ferroelectric KNN-based crystals. Comptes Rendus. Physique, 2013, 14 (2-3), pp.133-140. ⟨10.1016/j.crhy.2012.10.002⟩. ⟨hal-03898249⟩